Kinetics of the reduction of inorganic ions by borohydride—I ferricyanide

Highly Active Nanoreactors: Nanomaterial Encapsulation Based on Confined Catalysis

“…As the activation energy for the noncatalyzed reaction is 30 kJ mol À1 , [34] the results obtained (Supporting Information, Figure S2) indicate a remarkable catalytic activity of these hybrid nanocomposites. Thus, a value of 12.6 AE 1.2 kJ mol À1 was obtained for the redox process in the presence of the PS/Ptd composites, while a value of 12.3 AE 0.8 kJ mol À1 was achieved for the reaction catalyzed by Ptd/SiO 2 capsules.…”

“…Thus, a value of 12.6 AE 1.2 kJ mol À1 was obtained for the redox process in the presence of the PS/Ptd composites, while a value of 12.3 AE 0.8 kJ mol À1 was achieved for the reaction catalyzed by Ptd/SiO 2 capsules. As the activation energy for the noncatalyzed reaction is 30 kJ mol À1 , [34] the results obtained (Supporting Information, Figure S2) indicate a remarkable catalytic activity of these hybrid nanocomposites.…”

“…The energy barrier for this reaction is rather high (30 kJ mol À1 ) if uncatalyzed, [34] but the presence of PS/ Pt(s) composites lowers this value to 17.1 AE 1.1 kJ mol À1 . The widely reported and broadly studied Pt s nanoparticles, synthesized by reduction with NaBH 4 and stabilized through sodium citrate adsorption, can be considered as the model or reference system.…”

Mechanisms of chemical generation of volatile hydrides for trace element determination (IUPAC Technical Report)

“…Another reaction presenting a certain degree of complexity is that of THB with IO 3 -, which has been investigated under alkaline conditions [177]. Freund [178] investigated the mechanism and kinetics of reduction of hexacyanoferrate(III) by THB in the pH range from 9 to 13, which produces boric acid and ferrocyanide as the final products. For this reaction, the rate of disappearance of ferricyanide was found to be d[Fe(CN) 6 3-]/dt = k [BH 4 -] [H + ] with k = 5.1 × 10 6 L mol -1 s -1 at 25 °C, and independent of ferricyanide concentration.…”

“…As such, both species could be active as donors during THB hydrolysis and they can also act as chelating species for lead during plumbane formation. Another possibility which emerges from the studies of Freund [178] is that ferricyanide could oxidize the intermediates of THB hydrolysis through alternative one-and twoelectron reactions. For example, the intermediate BH 2 …”